A kind of continuous response hydrogen array gas-sensitive sensor
Technical field
The utility model belongs to hydrogen gas sensor technical field, and in particular to a kind of continuous response hydrogen array air-sensitive biography
Sensor.
Background technique
Hydrogen sensor can be divided into optical type and two kinds of electrical characteristics type.Wherein, optical type hydrogen sensor utilizes hydrogenation material
Expect that changes in optical properties of the film after inhaling hydrogen realizes the detection of hydrogen.Such sensor has high safety, high sensitivity
Advantage is disadvantageous in that test macro complexity, low-response, not easy operation control, and the service life is shorter.Electrical characteristics type hydrogen sensor
Testing principle be to show the catalysis reactiveness of hydrogen on the electrode as electronic signals, to obtain hydrogen
Fraction.Electrical characteristics type hydrogen sensor have it is easy to operate, be easily achieved micromation and it is integrated, can be the Maintenance free the case where
Lower long-time service.
The disadvantages of that there are response signals is small for traditional electrical characteristics detection mode, and sensitivity is low, poor anti jamming capability.Therefore right
The raising signal strength of electrical characteristics type hydrogen sensor and research work on anti-interference ability are numerous.It mainly include the quick material of hydrogen
Chemical constituent, binding performance, the quick material of hydrogen alloy and it is structural angularly, such as in Chinese patent CN102313761A
It discloses multiple groups Pd material electrodes to realize, forms a variety of different plane electrode spacing, spacing width value, which meets, waits differences
Column, the electrode of every kind of same widths include multiple shunt electrodes groups, form one group of hydrogen measure loop.Utilize the nanometer of small scale
Seam improves the sensitivity of sensor, and large scale nano-seam improves the measurement range of sensor, but this scheme cannot achieve hydrogen
The continuous response of material, and be arranged in parallel with size and the configuration of electrodes of arithmetic progression arrangement Different electrodes spacing increases
The difficulty of manufacture, improves cost.
Utility model content
The utility model provides a kind of continuous response hydrogen array gas-sensitive sensor and preparation method thereof, to solve
Hydrogen gas sensor the problems such as there are sensitivity, measurement range, continuity and practicabilities at present.
In order to solve the above-mentioned technical problem, the technical solution of the utility model is: the continuous response hydrogen array gas
Dependent sensor comprising substrate and the Pd material nano being arranged in substrate stitch electrode layer, and the Pd material nano stitches electrode layer
Including several strip Pd material strips for being arranged successively and the electrode for being plated in outermost Pd material strips, between adjacent Pd material strips
Gap width passes through as consecutive variations.
Optionally, the gap width between the adjacent Pd material strips passes through as by width to narrow linear change
Change.
In the environment of no hydrogen, since Pd is low resistance metal phase, there are spacing between Pd material, do not contact each other,
Entire sensor is not turned on, and state of insulation is between two electrodes.When sensor exposes in the hydrogen gas atmosphere, Pd encounters hydrogen
Palladium base hydride PdH is formed after gasx, due to HILE effect, palladium base hydride films expand so that there are the Pd material phases of spacing
It connects, forms a size and begun to turn between the micro-machinery switch of micron dimension, two electrodes, so that hydrogen is detected, by
It is gradually broadened in spacing, with increasing for density of hydrogen, palladium base hydride films expand more, and the spacing that can be filled and led up is got over
Width, so that the contact between Pd material is gradually increased, the also just linear reduction therewith of the resistance between two electrodes, to obtain
Resistance value is obtained to increase and reduced linear response with density of hydrogen.One group of electrode also need to be only set compared with prior art
Realize the effect of enhancing in parallel.
Optionally, the substrate includes the silica coating of silicon base and plating on a silicon substrate, and the silicon base is adopted
Silicon substrate micro-nano striped is formed with photoetching technique, silicon substrate micro-nano striped and Pd material strips correspond, the Pd material strips covering two
On membranous layer of silicon oxide.
Optionally, the silicon base thickness is greater than 200 microns, and the silicon substrate micro-nano striped is formed using photoetching technique, silicon
The etching depth of base micro-nano stripe layer is 50~100 microns.
Optionally, the silica coating is with a thickness of 100~1000 nanometers.
Optionally, the Pd material strips are wedge shaped, and all most wide one end of Pd material strips are located on side, the most narrow same position in one end
In the other side.
Optionally, the size of the Pd material strips is identical, and the gap between adjacent Pd material strips is wedge shaped.
Optionally, the most narrow place in the gap is 0~10 nanometer, and the widest part is 10~1000 nanometers.
Optionally, the Pd material strips are identical as the gap size.
The utility model additionally provides the preparation method of above-mentioned continuous response hydrogen array gas-sensitive sensor comprising such as
Lower step: depositing Pd material coating first in substrate, and the Pd material of array arrangement is then prepared using ultraviolet light photoetching technique
Material strip finally plates metal electrode in outermost Pd material strips.
Optionally, the substrate is to be overplated with silicon dioxide film on a silicon substrate as substrate.
Minimum hydrogen detection concentration is determined by the minimum spacing of wedge-shaped crevice in technical solution provided by the utility model, wedge
The slope in shape gap then controls the speed of resistance of sensor reduction, i.e. response sensitivity, and the power of detectable signal can pass through
The quantity of array striped is adjusted, and experiment shows that the sensor can be lower than 1ppm to the detection limit of hydrogen, and its resistance value is with hydrogen
Gas concentration is linear response.
Detailed description of the invention
Fig. 1 is the structural representation of one specific embodiment of continuous response hydrogen array gas-sensitive sensor described in the utility model
Figure;
Fig. 2 is the top view of Fig. 1.
It is as shown in the figure:
10- silicon base, 11- silicon substrate micro-nano striped, 20- silica coating, 30-Pd material nano stitch electrode layer, 31-Pd
Material strips, 32- electrode, the gap 40-.
Specific embodiment
In order to make it easy to understand, illustrating the continuous response hydrogen array gas-sensitive sensor, Ying Li below with reference to embodiment
Solution, these embodiments are merely to illustrate the utility model rather than limitation the scope of the utility model.
It is in the description of the present invention, it should be noted that term " center ", "upper", "lower", "left", "right", " perpendicular
Directly ", the orientation or positional relationship of the instructions such as "horizontal", "inner", "outside" is orientation based on the figure and positional relationship, is only
For ease of description the utility model and simplify description, rather than the device or element of indication or suggestion meaning must have it is specific
Orientation, be constructed and operated in a specific orientation, therefore should not be understood as limiting the present invention.In addition, term " the
One ", " second ", " third " are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance.
In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, term " is pacified
Dress ", " connected ", " connection " shall be understood in a broad sense, for example, it may be fixedly connected, may be a detachable connection or integrally
Connection;It can be mechanical connection, be also possible to be electrically connected;Can be directly connected, can also indirectly connected through an intermediary,
It can be the connection inside two elements.For the ordinary skill in the art, above-mentioned art can be understood with concrete condition
The concrete meaning of language in the present invention.
As shown in Figure 1, the continuous response hydrogen array gas-sensitive sensor, be silicon base 10 be overplated with a thickness of
Then 800 nanometers of silica coating 20 deposits Pd material coating, using ultraviolet light photoetching skill on silica coating 20
Art makes wedge-shaped crevice 40 by lithography, to form silicon substrate micro-nano striped 11, the dioxy that etch depth is 100 microns in silicon base 10
Electrode layer 30 is stitched for Pd material nano in SiClx film layer 20,10 overall thickness of silicon base is up to 200 microns.
As shown in Fig. 2, the Pd material nano seam electrode layer 30 includes several strip Pd materials from left to right successively arranged
Material strip 31 and the electrode 32 being plated in the Pd material strips 31 of the leftmost side and the rightmost side.
As illustrated in fig. 1 and 2, the silicon substrate micro-nano striped 11 is corresponded with Pd material strips 31, be based on process as it can be seen that
The Pd material strips 31 are identical as the cross section of corresponding silicon substrate micro-nano striped 11, all wedge shaped.
As shown in Fig. 2, the structure size of the Pd material strips 31 is identical, most wide one end is located on upside, and most narrow one end is same
Positioned at downside, convenient for arrangement and processing, the gap 40 between the adjacent Pd material strips 31 of formation is complementary with 31 shape of Pd material strips,
It is also wedge shape, it is preferable that Pd material strips 31 are identical as the size of wedge-shaped crevice 40.
The most narrow place of the wedge-shaped crevice 40 is 2 nanometers, and the widest part is 1000 nanometers.Experiments verify that density of hydrogen is visited
The density of hydrogen that the range of survey is 1~40000ppm changes, and steady change data can be detected, the variation of institute's measuring resistance value should be with
The reduction of wedge-shaped crevice is in continuous response, can accurately calculate density of hydrogen according to resistance value.
It should be pointed out that the present embodiment only provides the structure explanation of a row Pd material strips 31, actually can according to need
The mode for carrying out multiple rows of multiple row is configured, and the structure in gap 40 is also not necessarily limited to wedge shape, other are extended linear by this design
Variation belongs to the utility model scope.
In addition, can be at 100-1000 nanometers, silicon substrate micro-nano striped 11 be etched for the thickness of silica coating 20
Depth can be 50-100 microns, and the overall thickness of the silicon base 10 need to be up to 200 microns or more, and the most narrow place in the gap can be set
It is calculated as 0~10 nanometer, the widest part can design 10~1000 nanometers.
Finally, it should be noted that above embodiments are only to illustrate the technical solution of the utility model, rather than its limitations.
Although the utility model is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that:
It can still modify to technical solution documented by previous embodiment, or to some or all of the technical features
It is equivalently replaced, and these modifications or substitutions, various embodiments of the utility model that it does not separate the essence of the corresponding technical solution
The range of technical solution.